contrib/ldns/host2wire.c

   1 /*
   2  * host2wire.c
   3  *
   4  * conversion routines from the host to the wire format.
   5  * This will usually just a re-ordering of the
   6  * data (as we store it in network format)
   7  *
   8  * a Net::DNS like library for C
   9  *
  10  * (c) NLnet Labs, 2004-2006
  11  *
  12  * See the file LICENSE for the license
  13  */
  14
  15 #include <ldns/config.h>
  16
  17 #include <ldns/ldns.h>
  18
  19 ldns_status
  20 ldns_dname2buffer_wire(ldns_buffer *buffer, const ldns_rdf *name)
  21 {
  22         return ldns_dname2buffer_wire_compress(buffer, name, NULL);
  23 }
  24
  25 ldns_status
  26 ldns_dname2buffer_wire_compress(ldns_buffer *buffer, const ldns_rdf *name, ldns_rbtree_t *compression_data)
  27 {
  28         ldns_rbnode_t *node;
  29         uint8_t *data;
  30         size_t size;
  31         ldns_rdf *label;
  32         ldns_rdf *rest;
  33         ldns_status s;
  34
  35         /* If no tree, just add the data */
  36         if(!compression_data)
  37         {
  38                 if (ldns_buffer_reserve(buffer, ldns_rdf_size(name)))
  39                 {
  40                         ldns_buffer_write(buffer, ldns_rdf_data(name), ldns_rdf_size(name));
  41                 }
  42                 return ldns_buffer_status(buffer);
  43         }
  44
  45         /* No labels left, write final zero */
  46         if(ldns_dname_label_count(name)==0)
  47         {
  48                 if(ldns_buffer_reserve(buffer,1))
  49                 {
  50                         ldns_buffer_write_u8(buffer, 0);
  51                 }
  52                 return ldns_buffer_status(buffer);
  53         }
  54
  55         /* Can we find the name in the tree? */
  56         if((node = ldns_rbtree_search(compression_data, name)) != NULL)
  57         {
  58                 /* Found */
  59                 uint16_t position = (uint16_t) (intptr_t) node->data | 0xC000;
  60                 if (ldns_buffer_reserve(buffer, 2))
  61                 {
  62                         ldns_buffer_write_u16(buffer, position);
  63                 }
  64                 return ldns_buffer_status(buffer);
  65         }
  66         else
  67         {
  68                 /* Not found. Write cache entry, take off first label, write it, */
  69                 /* try again with the rest of the name. */
  70                 node = LDNS_MALLOC(ldns_rbnode_t);
  71                 if(!node)
  72                 {
  73                         return LDNS_STATUS_MEM_ERR;
  74                 }
  75                 if (ldns_buffer_position(buffer) < 16384) {
  76                         node->key = ldns_rdf_clone(name);
  77                         node->data = (void *) (intptr_t) ldns_buffer_position(buffer);
  78                         if(!ldns_rbtree_insert(compression_data,node))
  79                         {
  80                                 /* fprintf(stderr,"Name not found but now it's there?\n"); */
  81                         }
  82                 }
  83                 label = ldns_dname_label(name, 0);
  84                 rest = ldns_dname_left_chop(name);
  85                 size = ldns_rdf_size(label) - 1; /* Don't want the final zero */
  86                 data = ldns_rdf_data(label);
  87                 if(ldns_buffer_reserve(buffer, size))
  88                 {
  89                         ldns_buffer_write(buffer, data, size);
  90                 }
  91                 ldns_rdf_deep_free(label);
  92                 s = ldns_dname2buffer_wire_compress(buffer, rest, compression_data);
  93                 ldns_rdf_deep_free(rest);
  94                 return s;
  95         }
  96 }
  97
  98 ldns_status
  99 ldns_rdf2buffer_wire(ldns_buffer *buffer, const ldns_rdf *rdf)
 100 {
 101         return ldns_rdf2buffer_wire_compress(buffer, rdf, NULL);
 102 }
 103
 104 ldns_status
 105 ldns_rdf2buffer_wire_compress(ldns_buffer *buffer, const ldns_rdf *rdf, ldns_rbtree_t *compression_data)
 106 {
 107         /* If it's a DNAME, call that function to get compression */
 108         if(compression_data && ldns_rdf_get_type(rdf) == LDNS_RDF_TYPE_DNAME)
 109         {
 110                 return ldns_dname2buffer_wire_compress(buffer,rdf,compression_data);
 111         }
 112
 113         if (ldns_buffer_reserve(buffer, ldns_rdf_size(rdf))) {
 114                 ldns_buffer_write(buffer, ldns_rdf_data(rdf), ldns_rdf_size(rdf));
 115         }
 116         return ldns_buffer_status(buffer);
 117 }
 118
 119 ldns_status
 120 ldns_rdf2buffer_wire_canonical(ldns_buffer *buffer, const ldns_rdf *rdf)
 121 {
 122         size_t i;
 123         uint8_t *rdf_data;
 124
 125         if (ldns_rdf_get_type(rdf) == LDNS_RDF_TYPE_DNAME) {
 126                 if (ldns_buffer_reserve(buffer, ldns_rdf_size(rdf))) {
 127                         rdf_data = ldns_rdf_data(rdf);
 128                         for (i = 0; i < ldns_rdf_size(rdf); i++) {
 129                                 ldns_buffer_write_u8(buffer,
 130                                     (uint8_t) LDNS_DNAME_NORMALIZE((int)rdf_data[i]));
 131                         }
 132                 }
 133         } else {
 134                 /* direct copy for all other types */
 135                 if (ldns_buffer_reserve(buffer, ldns_rdf_size(rdf))) {
 136                         ldns_buffer_write(buffer,
 137                                                    ldns_rdf_data(rdf),
 138                                                    ldns_rdf_size(rdf));
 139                 }
 140         }
 141         return ldns_buffer_status(buffer);
 142 }
 143
 144 /* convert a rr list to wireformat */
 145 ldns_status
 146 ldns_rr_list2buffer_wire(ldns_buffer *buffer,const ldns_rr_list *rr_list)
 147 {
 148         uint16_t rr_count;
 149         uint16_t i;
 150
 151         rr_count = ldns_rr_list_rr_count(rr_list);
 152         for(i = 0; i < rr_count; i++) {
 153                 (void)ldns_rr2buffer_wire(buffer, ldns_rr_list_rr(rr_list, i),
 154                                           LDNS_SECTION_ANY);
 155         }
 156         return ldns_buffer_status(buffer);
 157 }
 158
 159
 160 ldns_status
 161 ldns_rr2buffer_wire_canonical(ldns_buffer *buffer,
 162                                                 const ldns_rr *rr,
 163                                                 int section)
 164 {
 165         uint16_t i;
 166         uint16_t rdl_pos = 0;
 167         bool pre_rfc3597 = false;
 168         switch (ldns_rr_get_type(rr)) {
 169         case LDNS_RR_TYPE_NS:
 170         case LDNS_RR_TYPE_MD:
 171         case LDNS_RR_TYPE_MF:
 172         case LDNS_RR_TYPE_CNAME:
 173         case LDNS_RR_TYPE_SOA:
 174         case LDNS_RR_TYPE_MB:
 175         case LDNS_RR_TYPE_MG:
 176         case LDNS_RR_TYPE_MR:
 177         case LDNS_RR_TYPE_PTR:
 178         case LDNS_RR_TYPE_HINFO:
 179         case LDNS_RR_TYPE_MINFO:
 180         case LDNS_RR_TYPE_MX:
 181         case LDNS_RR_TYPE_RP:
 182         case LDNS_RR_TYPE_AFSDB:
 183         case LDNS_RR_TYPE_RT:
 184         case LDNS_RR_TYPE_SIG:
 185         case LDNS_RR_TYPE_PX:
 186         case LDNS_RR_TYPE_NXT:
 187         case LDNS_RR_TYPE_NAPTR:
 188         case LDNS_RR_TYPE_KX:
 189         case LDNS_RR_TYPE_SRV:
 190         case LDNS_RR_TYPE_DNAME:
 191         case LDNS_RR_TYPE_A6:
 192         case LDNS_RR_TYPE_RRSIG:
 193                 pre_rfc3597 = true;
 194                 break;
 195         default:
 196                 break;
 197         }
 198
 199         if (ldns_rr_owner(rr)) {
 200                 (void) ldns_rdf2buffer_wire_canonical(buffer, ldns_rr_owner(rr));
 201         }
 202
 203         if (ldns_buffer_reserve(buffer, 4)) {
 204                 (void) ldns_buffer_write_u16(buffer, ldns_rr_get_type(rr));
 205                 (void) ldns_buffer_write_u16(buffer, ldns_rr_get_class(rr));
 206         }
 207
 208         if (section != LDNS_SECTION_QUESTION) {
 209                 if (ldns_buffer_reserve(buffer, 6)) {
 210                         ldns_buffer_write_u32(buffer, ldns_rr_ttl(rr));
 211                         /* remember pos for later */
 212                         rdl_pos = ldns_buffer_position(buffer);
 213                         ldns_buffer_write_u16(buffer, 0);
 214                 }
 215                 for (i = 0; i < ldns_rr_rd_count(rr); i++) {
 216                         if (pre_rfc3597) {
 217                                 (void) ldns_rdf2buffer_wire_canonical(
 218                                         buffer, ldns_rr_rdf(rr, i));
 219                         } else {
 220                                 (void) ldns_rdf2buffer_wire(
 221                                         buffer, ldns_rr_rdf(rr, i));
 222                         }
 223                 }
 224                 if (rdl_pos != 0) {
 225                         ldns_buffer_write_u16_at(buffer, rdl_pos,
 226                                                  ldns_buffer_position(buffer)
 227                                                    - rdl_pos - 2);
 228                 }
 229         }
 230         return ldns_buffer_status(buffer);
 231 }
 232
 233 ldns_status
 234 ldns_rr2buffer_wire(ldns_buffer *buffer, const ldns_rr *rr, int section)
 235 {
 236         return ldns_rr2buffer_wire_compress(buffer,rr,section,NULL);
 237 }
 238
 239 ldns_status
 240 ldns_rr2buffer_wire_compress(ldns_buffer *buffer, const ldns_rr *rr, int section, ldns_rbtree_t *compression_data)
 241 {
 242         uint16_t i;
 243         uint16_t rdl_pos = 0;
 244
 245         if (ldns_rr_owner(rr)) {
 246                 (void) ldns_dname2buffer_wire_compress(buffer, ldns_rr_owner(rr), compression_data);
 247         }
 248
 249         if (ldns_buffer_reserve(buffer, 4)) {
 250                 (void) ldns_buffer_write_u16(buffer, ldns_rr_get_type(rr));
 251                 (void) ldns_buffer_write_u16(buffer, ldns_rr_get_class(rr));
 252         }
 253
 254         if (section != LDNS_SECTION_QUESTION) {
 255                 if (ldns_buffer_reserve(buffer, 6)) {
 256                         ldns_buffer_write_u32(buffer, ldns_rr_ttl(rr));
 257                         /* remember pos for later */
 258                         rdl_pos = ldns_buffer_position(buffer);
 259                         ldns_buffer_write_u16(buffer, 0);
 260                 }
 261                 if (LDNS_RR_COMPRESS ==
 262                     ldns_rr_descript(ldns_rr_get_type(rr))->_compress) {
 263
 264                         for (i = 0; i < ldns_rr_rd_count(rr); i++) {
 265                                 (void) ldns_rdf2buffer_wire_compress(buffer,
 266                                     ldns_rr_rdf(rr, i), compression_data);
 267                         }
 268                 } else {
 269                         for (i = 0; i < ldns_rr_rd_count(rr); i++) {
 270                                 (void) ldns_rdf2buffer_wire(
 271                                     buffer, ldns_rr_rdf(rr, i));
 272                         }
 273                 }
 274                 if (rdl_pos != 0) {
 275                         ldns_buffer_write_u16_at(buffer, rdl_pos,
 276                                                  ldns_buffer_position(buffer)
 277                                                    - rdl_pos - 2);
 278                 }
 279         }
 280         return ldns_buffer_status(buffer);
 281 }
 282
 283 ldns_status
 284 ldns_rrsig2buffer_wire(ldns_buffer *buffer, const ldns_rr *rr)
 285 {
 286         uint16_t i;
 287
 288         /* it must be a sig RR */
 289         if (ldns_rr_get_type(rr) != LDNS_RR_TYPE_RRSIG) {
 290                 return LDNS_STATUS_ERR;
 291         }
 292
 293         /* Convert all the rdfs, except the actual signature data
 294          * rdf number 8  - the last, hence: -1 */
 295         for (i = 0; i < ldns_rr_rd_count(rr) - 1; i++) {
 296                 (void) ldns_rdf2buffer_wire_canonical(buffer,
 297                                 ldns_rr_rdf(rr, i));
 298         }
 299
 300         return ldns_buffer_status(buffer);
 301 }
 302
 303 ldns_status
 304 ldns_rr_rdata2buffer_wire(ldns_buffer *buffer, const ldns_rr *rr)
 305 {
 306         uint16_t i;
 307
 308         /* convert all the rdf's */
 309         for (i = 0; i < ldns_rr_rd_count(rr); i++) {
 310                 (void) ldns_rdf2buffer_wire(buffer, ldns_rr_rdf(rr,i));
 311         }
 312         return ldns_buffer_status(buffer);
 313 }
 314
 315 /*
 316  * Copies the packet header data to the buffer in wire format
 317  */
 318 static ldns_status
 319 ldns_hdr2buffer_wire(ldns_buffer *buffer, const ldns_pkt *packet)
 320 {
 321         uint8_t flags;
 322         uint16_t arcount;
 323
 324         if (ldns_buffer_reserve(buffer, 12)) {
 325                 ldns_buffer_write_u16(buffer, ldns_pkt_id(packet));
 326
 327                 flags = ldns_pkt_qr(packet) << 7
 328                         | ldns_pkt_get_opcode(packet) << 3
 329                         | ldns_pkt_aa(packet) << 2
 330                         | ldns_pkt_tc(packet) << 1 | ldns_pkt_rd(packet);
 331                 ldns_buffer_write_u8(buffer, flags);
 332
 333                 flags = ldns_pkt_ra(packet) << 7
 334                         /*| ldns_pkt_z(packet) << 6*/
 335                         | ldns_pkt_ad(packet) << 5
 336                         | ldns_pkt_cd(packet) << 4
 337                         | ldns_pkt_get_rcode(packet);
 338                 ldns_buffer_write_u8(buffer, flags);
 339
 340                 ldns_buffer_write_u16(buffer, ldns_pkt_qdcount(packet));
 341                 ldns_buffer_write_u16(buffer, ldns_pkt_ancount(packet));
 342                 ldns_buffer_write_u16(buffer, ldns_pkt_nscount(packet));
 343                 /* add EDNS0 and TSIG to additional if they are there */
 344                 arcount = ldns_pkt_arcount(packet);
 345                 if (ldns_pkt_tsig(packet)) {
 346                         arcount++;
 347                 }
 348                 if (ldns_pkt_edns(packet)) {
 349                         arcount++;
 350                 }
 351                 ldns_buffer_write_u16(buffer, arcount);
 352         }
 353
 354         return ldns_buffer_status(buffer);
 355 }
 356
 357 static void
 358 compression_node_free(ldns_rbnode_t *node, void *arg)
 359 {
 360         (void)arg; /* Yes, dear compiler, it is used */
 361         ldns_rdf_deep_free((ldns_rdf *)node->key);
 362         LDNS_FREE(node);
 363 }
 364
 365 ldns_status
 366 ldns_pkt2buffer_wire(ldns_buffer *buffer, const ldns_pkt *packet)
 367 {
 368         ldns_rr_list *rr_list;
 369         uint16_t i;
 370
 371         /* edns tmp vars */
 372         ldns_rr *edns_rr;
 373         uint8_t edata[4];
 374
 375         ldns_rbtree_t *compression_data = ldns_rbtree_create((int (*)(const void *, const void *))ldns_dname_compare);
 376
 377         (void) ldns_hdr2buffer_wire(buffer, packet);
 378
 379         rr_list = ldns_pkt_question(packet);
 380         if (rr_list) {
 381                 for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
 382                         (void) ldns_rr2buffer_wire_compress(buffer,
 383                                      ldns_rr_list_rr(rr_list, i), LDNS_SECTION_QUESTION, compression_data);
 384                 }
 385         }
 386         rr_list = ldns_pkt_answer(packet);
 387         if (rr_list) {
 388                 for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
 389                         (void) ldns_rr2buffer_wire_compress(buffer,
 390                                      ldns_rr_list_rr(rr_list, i), LDNS_SECTION_ANSWER, compression_data);
 391                 }
 392         }
 393         rr_list = ldns_pkt_authority(packet);
 394         if (rr_list) {
 395                 for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
 396                         (void) ldns_rr2buffer_wire_compress(buffer,
 397                                      ldns_rr_list_rr(rr_list, i), LDNS_SECTION_AUTHORITY, compression_data);
 398                 }
 399         }
 400         rr_list = ldns_pkt_additional(packet);
 401         if (rr_list) {
 402                 for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
 403                         (void) ldns_rr2buffer_wire_compress(buffer,
 404                                      ldns_rr_list_rr(rr_list, i), LDNS_SECTION_ADDITIONAL, compression_data);
 405                 }
 406         }
 407
 408         /* add EDNS to additional if it is needed */
 409         if (ldns_pkt_edns(packet)) {
 410                 edns_rr = ldns_rr_new();
 411                 if(!edns_rr) return LDNS_STATUS_MEM_ERR;
 412                 ldns_rr_set_owner(edns_rr,
 413                                 ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, "."));
 414                 ldns_rr_set_type(edns_rr, LDNS_RR_TYPE_OPT);
 415                 ldns_rr_set_class(edns_rr, ldns_pkt_edns_udp_size(packet));
 416                 edata[0] = ldns_pkt_edns_extended_rcode(packet);
 417                 edata[1] = ldns_pkt_edns_version(packet);
 418                 ldns_write_uint16(&edata[2], ldns_pkt_edns_z(packet));
 419                 ldns_rr_set_ttl(edns_rr, ldns_read_uint32(edata));
 420                 /* don't forget to add the edns rdata (if any) */
 421                 if (packet->_edns_data)
 422                         ldns_rr_push_rdf (edns_rr, packet->_edns_data);
 423                 (void)ldns_rr2buffer_wire_compress(buffer, edns_rr, LDNS_SECTION_ADDITIONAL, compression_data);
 424                 /* take the edns rdata back out of the rr before we free rr */
 425                 if (packet->_edns_data)
 426                         (void)ldns_rr_pop_rdf (edns_rr);
 427                 ldns_rr_free(edns_rr);
 428         }
 429
 430         /* add TSIG to additional if it is there */
 431         if (ldns_pkt_tsig(packet)) {
 432                 (void) ldns_rr2buffer_wire_compress(buffer,
 433                                            ldns_pkt_tsig(packet), LDNS_SECTION_ADDITIONAL, compression_data);
 434         }
 435
 436         ldns_traverse_postorder(compression_data,compression_node_free,NULL);
 437         ldns_rbtree_free(compression_data);
 438
 439         return LDNS_STATUS_OK;
 440 }
 441
 442 ldns_status
 443 ldns_rdf2wire(uint8_t **dest, const ldns_rdf *rdf, size_t *result_size)
 444 {
 445         ldns_buffer *buffer = ldns_buffer_new(LDNS_MAX_PACKETLEN);
 446         ldns_status status;
 447         *result_size = 0;
 448         *dest = NULL;
 449         if(!buffer) return LDNS_STATUS_MEM_ERR;
 450
 451         status = ldns_rdf2buffer_wire(buffer, rdf);
 452         if (status == LDNS_STATUS_OK) {
 453                 *result_size =  ldns_buffer_position(buffer);
 454                 *dest = (uint8_t *) ldns_buffer_export(buffer);
 455         }
 456         ldns_buffer_free(buffer);
 457         return status;
 458 }
 459
 460 ldns_status
 461 ldns_rr2wire(uint8_t **dest, const ldns_rr *rr, int section, size_t *result_size)
 462 {
 463         ldns_buffer *buffer = ldns_buffer_new(LDNS_MAX_PACKETLEN);
 464         ldns_status status;
 465         *result_size = 0;
 466         *dest = NULL;
 467         if(!buffer) return LDNS_STATUS_MEM_ERR;
 468
 469         status = ldns_rr2buffer_wire(buffer, rr, section);
 470         if (status == LDNS_STATUS_OK) {
 471                 *result_size =  ldns_buffer_position(buffer);
 472                 *dest = (uint8_t *) ldns_buffer_export(buffer);
 473         }
 474         ldns_buffer_free(buffer);
 475         return status;
 476 }
 477
 478 ldns_status
 479 ldns_pkt2wire(uint8_t **dest, const ldns_pkt *packet, size_t *result_size)
 480 {
 481         ldns_buffer *buffer = ldns_buffer_new(LDNS_MAX_PACKETLEN);
 482         ldns_status status;
 483         *result_size = 0;
 484         *dest = NULL;
 485         if(!buffer) return LDNS_STATUS_MEM_ERR;
 486
 487         status = ldns_pkt2buffer_wire(buffer, packet);
 488         if (status == LDNS_STATUS_OK) {
 489                 *result_size =  ldns_buffer_position(buffer);
 490                 *dest = (uint8_t *) ldns_buffer_export(buffer);
 491         }
 492         ldns_buffer_free(buffer);
 493         return status;
 494 }